Compressor



May 13, 1930. GREENWALD 1,757,997

@as JkZei I INVENTOR. 7%m2d A7. 'reemuald ATTORNEY5 Patented May 13,1930 UNITED STATES PATENT .OFFI'CE HAROLD A. GREENWALD, or DETROIT,MICHIGAN COMPRESSOR Application filed April 26,

expansible chamber. filled with a fluid, liq-' uid, semi-solid or solidor a combination of any two or more of these, for the purpose ofreducing the clearance space to render possible the compression of a gasto a higher pressure than would be otherwise possible.

The use of an elastic or expansible chamher as a piston and compressionchamber results in several noteworthy advantages, not the least of whichis the prevention of leakage of "the compressed gas past or around thepiston. Obviously in using such a chamber the ends thereof may bepermanently sealed so that-the gas entering therein to be compressed isprevented from escaping.

However, the use of an expansible or elastic chamber requires thesolution of several problems if such an apparatusis to function entirelysatisfactorily and efficiently. One of the more important of theseproblems is that of reducing the clearance space in the chamber so thatthe gas or the like may be compressed to the desired degree as obviouslytoo great clearance in the chamber will result in the attainment of onlya low pressure and a consequent inefficient pumping action.

Furthermore with elastic or expansible chambers, which are customarilyconstructed of metal or the like, it is necessary that the bending orflexing action transmitted or imparted to the several folds or pleatsof'the chamber, be of a degree wellwithin the elastic limits of thematerial so as to prevent fatigue and failure thereof. Consequently thegreatest efliciency is attained when the elastic or expansible chamberis of a relatively large size including a relatively large number offolds or pleats so that the flexing or bendmg of each pleat, during thecollapslngand eX- panding of the chambenis at a minimum. With arelatively large expansible chamber the need for a reduction in theclearance space 1926. Serial No. 104,758.

is more forcibly emphasized as otherwise the relative lnefficiency ofthe pumping operation would preclude its adoption commercial- Theinvention therefore contemplates an elastic or expansible chamberfilled, as aforesaid, with fluid, liquid, semi-solid or solid or acombination of two or more of any of these, for the purpose of reducingthe clearance space within the chamber so that as the chamher isexpanded and collapsed, the head constituted by the level of any of thefiller mediums aforementioned, will be displaced to compress and expelthe'gas or vapor as is customary in compressors of the conventionaldesigns.

WVhile it is readily apparent that the invention finds practical utilityin many types ofapparatus, it may be used to particular advantage inapparatus wherein it is desired to pump a gas or the like whereinspecial efforts are necessary to prevent a leakage of the gas past thepiston. Thus, the invention may be used to advantage inrefrigeratingapparatus as a compressor pump for compressing therefrigerant because in some characters of refrigerating apparatusconsiderable diiiiculty is experienced in preventing a leakage of therefrigerant past the piston of the compressor where it frequentlyescapes and mixes with the lubricant with consequential detrimentaleffect or escapes from the system. where the driving shaft goes throughcoinpressor housing.

Various other objects, advantages and novel details of construction ofthe invention will be made more apparent as this description proceeds,especially when considered in connection withthe accompanying drawingswherein two illustrative embodiments of the invention are shown andwherein The figure is a longitudinal sectional view through a pumpconstructed in accordance with my invention.

Referring now particularly to the figure, it will be noted that I haveshown a casing or jacket 10 constituting the outer housing of the pumpwhich may conveniently be supported as, for instance, by supporting legsor lugs 11 to a fixed support 12. The jacket 10 may be provided with oneor more ribs 13 to increase the radiating surface thereof for effectinga more efficient cooling and further with a removable closure 14 wherebythe interior of the jacket 10 may be filled with the oil or the likewhich not only constitutes a lubricating medium but also a coolingmedium for the parts immersed therein.

The reference character 15 indicates a casting including a circularplate-like head portion removably secured to the open end of the jacket10 and with a concentrically arranged portion 17 projecting interiorlyof the jacket 10. The end of the projecting portion 17 is here shown asshouldered to support a sleeve-like member 18 which is provided at itsupper end with a laterally extending flange or projection 19. Therelatively reduced end 20 of the extension 17 is likewise shouldered toreceive and support a sleeve-like element 21 provided at its upper edgewith an inwardly directed flange or extension 22.

The reference character 23 indicates a bellows or elastic or expansiblemember defining a chamber 24, this member being joined as at 25 to thehead 16 and as at 26 to a cup shaped cap member 27. Obviously the jointsand 26 will be sealed to prevent the escape of the contents of thechamber 24. The cap member 27 has a wrist pin connection 28 with aconnecting rod 29 connected to an eccentric 30 of a shaft 31. Upon therotation of the shaft 31 the connecting rod 29 will be verticallyreciprocated to impart a like motion to the cap member 27 which in turnwill expand and collapse the elastic chamber mem her 23.

The gas inlet nozzle is indicated by the reference character 32 andconnects with an annular passage formed in the extension 17. Thisannular passage communicates by one or more openings 34.- with anannular passage 35 provided by the spaced sleeves 18 and 21. The upperends of these sleeves adjacent the end of the annular passage are shapedto provide a valve seat for a valve 36, here shown as a gravity seatedring valve. The annular flange 22 on the sleeve member 21 is formed witha valve seat for a valve 37 which is herein shown as being held inseated position by means of a spring 38 bearing thereagainst and againsta nipple or lug 39 projecting from the end of the extension Thereference cl aracter 10 indicates a central bore or passage whichconnects with a nipple 41 and constitutes the gas outlet. The lateralflange 19 on the sleeve 18 extends to a point adjacent the circular sidewall of the cap member 27 but a clearance is provided between theseparts as the annular flange 19 functions purely as an anti-splashelement for the contents of the chamber 2% when liquid is employed.

The operation of this invention is as follows: The liquid or fluid isplaced in the chamber 24 to a level, for instance, substantiallycoincident with the lower surface of the annular flange 19 so as toreduce the clearance between the lower end of the expansible chamber andits upper end. hen, thereafter, the crank shaft 31 is rotated toreciprocate the cap member 27 the elastic element 23 will besuccessively expanded and collapsed, it being shown in the presentinstance in collapsed position. During the expanding movement the capmember 27 is moved upwardly and gas to be compressed is drawn in throughnipple 32, passage 33, openings 34. and passage 35 and past valve 36which is thereupon lifted and into the chamber defined by the cap member27 on the one hand and the level of the liquid L and the solid elements19 and 22 on the other. Upon the collapsing of the member 23 or themovement of the cap member 27 in a downward direction, the valve 36 willclose and the valve 37 will open against the pressure of spring 38 topermit the escape of the gas compressed upon this compression operationof the pump. The compressed gas will flow through the passage lO-and outthrough the nipple 41.

Obviously there is no likelihood whatsoever of the gas which enters theerpansible chamber leaking therefrom as the chamber is sealedthroughout. Consequently there is no loss of gas and no likelihood ofthe same becoming mixed with the lubricant or other medium whichsurrounds the expansible chamber and which is contained within thejacket 10. Obviously the continued expansion and collapsing of theelement 23 and the movement of the other parts will generate heat butthe lubricant contained within the jacket 10 will function effectivelyas a cooling medium in addition to lubricating the parts. The clearancein the expansible chamber may be varied at will by adding or removingthe medium L placed in the chamber 24. It will be noted that the innerdiameter of the cap 27 is somewhat less than the greatest diameter ofthe bellows so that upon the collapsing of the bellows the rise of themedium L will be at a faster rate than if the diameters of the aforesaidmembers were of the same size. In other words a long stroke of thepiston may be obtained by a relatively short stroke or movement of thebellows by such an arrangement.

It will be readily apparent that this provides for a more efficientoperation of the pump and greatly facilitates the compression of thematerial upon the downward movement of the cap and bellows.

The underlying principle of the present invention as disclosed in theillustrative embodiment herein shown and described, is capable ofexpression in numerous forms of construction and it should accordinglybe understood that no limitation should be imposed upon the invention byreason of any of the details of construction or specific arrangements ofparts herein shown and die scribed. Reservation is therefore made tomake such changes in the essential and all of the non-essential detailsof the invention as may come within the purview of the accompanyingclaims.

What I claim as my invention is:

1. In a compressor, a variable member cooperating with a portion of thecompressor to form a chamber wall for receiving and enclosing thematerial'to be compressed and a medium in said chamber for reducing theclearance space of said chamber.

2. In a compressor an expansible member cooperating with a portion ofthe compressor to form a chamber wall for receiving and enclosing thematerial to be compressed and a medium in said chamber for reducing theclearance space thereof.

3. In a compressor, a bellows-like member sealed at one end to a part ofthe compressor structure, a reciprocating element having a sealedconnection with the other end of said bellows-like member, saidbellows-like member and the said associated parts constituting the wallof a chamber for receiving the material to be compressed, and a mediumin said chamber for reducing the clearance space thereof.

4. In a compressor, a bellows-like member sealed at one end to a part ofthe compressor structure, a reciprocating element having a sealedconnection with the other end of said bellows-like member, saidbellows-like member and the said associated parts constituting the wallof a chamber for receiving the material to be compressed, a medium insaid chamber for reducing the clearance space thereof and means foractuating said reciproeating element to expand and collapse saidbellows-like member.

5. In a compressor construction, a bellowslike element'connectedrespectively to fixed and reciprocating parts of said compressor andconstituting therewith the wall of a chamber, a valve controlled inletand outlet passages communicating with said chamber and a medium forreducing the clearance space of said chamber.

6. In a compressor construction, a bellowslike element connectedrespectively to fixed and reciprocating parts of said compressor andconstituting therewith the wall of a chamber, valve controlled inlet andoutlet passages communicating with said chamber and fluid means forreducing the clearance space of said chamber.

7 In a compressor construction, a bellowslike element connectedrespectively to fixed and reciprocating parts of said compressor andconstituting therewith the wall of a chamber, valve controlled inlet andoutlet pasing the chamber for receiving the material" to be compressed,means in said chamber for reducing the clearance space thereof andconstituting a piston, the fluid piston being of greater diameter withinthe bellows-like member than above the same when said member isextended, whereby a long stroke of the piston maybe effected by arelatively short stroke of the bellows-like member.

9. In a compressor, a cylindrical bellowslike member sealed at one endto a part of the compressor structure, a cylindrical reciprm eatingelement having a sealed connection with the other end of saidbellows-like member, said bellows-like member and'the associated partsconstituting the chamber for receiving the material to be compressed, afluid in said chamber constituting a piston for compressing thematerial, the fluid piston being of greater diameter within thebellows-like member than above the same when said member is extendedwhereby a short stroke of said bellows-like member will produce arelatively long stroke of said piston.

10. In a compressor, a bellows-like member secured at one end to a partof the compressor structure, a cap-like element secured to the other endof said member and constituting therewith a chamber for receiving thematerial to be compressed, and filler means in said chamber for reducingthe clearance space thereof.

11. In a compressor, a bellows-like member secured at one end to a partof the compressor structure, a cap-like element secured to the other endof said member and constituting therewith a chamber for receiving thematerial to be compressed, filler means in said chamber for reducing theclearance space thereof, and means for expanding and collapslng saidbellows-like element including a part secured to said cap-like element.

12. In a compressor, a bellows-like member secured at one end to a partof the compressor structure, a cap-like element secured to the other endof said member and constituting therewith a chamber for receiving thematerial to be compressed, filler means in said chamber for reducing theclearance space thereof, valve controlled inlet and outlet passagescommunicating with said chamber adjacent said cap-like element, andmeans for reducing the clearance space of said chamber.

13. In a compressor, a bellows-like member secuT'ed'at one end to apartlofthe compressor stm'ctur'e'; n cup-alikeelementseoured to thoother' end of said in'einber and constituting therewith a chamber forreceiving the mate nial t0 be compressed, filler means in saidoh'smberfoireducing the clearance" space thereofgancl constitutinglafluid pistonidr compressing the matei'ial in said chamber.

14:; I11 a deviceof the class described, a bel-' wlOWSfEtPlStOlTillT-OIIG end of and op'eratively com-tectecltosaid bellows, aniedium within thebellows nnd'substztntially fillingthe samewhencontractetlyand means operable when the-bellows isexpanded-for"admitting a fluidsbetween the'pistorr and the hendof themedium whereby "as thebellows is againtonttactedthe fluid wi'll becompressed between said head and piston.

lfi Ina device of the class described, a 20T;fi1\'(l part und=ureeiproeating purt, a-contraetible and--expnnsible bellows terminallyconneetedto said parts, a medium Within the bellows and substantiallyfilling the same when contracted, Y and means operable when gmthe'bell0ws is expanded fol-"admitting a fluid between thereciprocating partzmlthe head of-thoqnedium, wherebyas the bel-lows isagain contract-ed the fluid will be compressed betweensaid head andpiston. 30 In testimony whereof I affix my signature;

HAROLD A.- GREENNVALD;

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